LOS ANGELES (AP) — Jennifer Lawrence has contacted authorities to investigate who stole and posted nude images of the Oscar winner online, a publicist for the actress said.

Intimate images of the actress, who stars in "The Hunger Games" film franchise and won an Academy Award for her role in "Silver Linings Playbook," began appearing online on Sunday. Naked images purporting to be of other female stars were also posted, although the authenticity of many of the images could not be confirmed. The source of the leak was unclear.

"This is a flagrant violation of privacy," Lawrence's publicist Liz Mahoney wrote in a statement. "The authorities have been contacted and will prosecute anyone who posts the stolen photos of Jennifer Lawrence."

Mahoney declined to provide further details, including which authorities were contacted. Lawrence, 24, is a three-time Oscar nominee.

How widespread the hacking of celebrities photos was is not immediately clear. Some of the images were quickly denounced as fakes.

Some cybersecurity experts speculated that hackers may have obtained a cache of private celebrity images by exploiting weaknesses in an online image-storing platform.

"It is important for celebrities and the general public to remember that images and data no longer just reside on the device that captured it," security researcher Ken Westin wrote in a blog post Monday. "Once images and other data are uploaded to the cloud, it becomes much more difficult to control who has access to it, even if we think it is private."

Private information and images of celebrities are frequent targets for hackers. Last year, a site posted credit reports, Social Security numbers and other financial info on celebrities, including Jay Z and his wife Beyonce, Mel Gibson, Ashton Kutcher and many others.

Johansson, Kunis and Aguilera were hacked by a Florida man, Christopher Chaney, who used publicly available information to hack into the email accounts of more than 50 people in the entertainment industry.

"I have been truly humiliated and embarrassed," Johansson said in a tearful videotaped statement played in court at Chaney's sentencing in December 2012.

"That feeling of security can never be given back and there is no compensation that can restore the feeling one has from such a large invasion of privacy," Aguilera wrote in a statement before Chaney's sentencing.